Thanks for that, I didn't think about that at allBottle holder on your bike is located quite low. To install battery on downtube you might need to buy this:
E-Bike Battery Installation Adjustment Bracket ONLY for Hailong Battery
1.Technical DataFit for: 36V/48V Hailong batteries in these links.https://yosepower.com/products/36v-13ah-down-tube-batteryhttps://yosepower.com/products/36v-13ah-hailong-li-ion-e-bike-battery-with-4-pins-plughttps://yosepower.com/products/36v15ah-36v17-4ah-48v12-5ah-down-tube-battery2.Packing...yosepower.com